The invention relates to a dosing device for the addition of an additive to a treatment chamber, in particular for a water-carrying household appliance, wherein the additive can be added to the treatment chamber by means of a conveying device driven by at least one actuator. The invention further relates to a dishwasher machine provided with a dosing device of this type.
Additives are required for all process or program steps, in particular for the “cleaning” process step in dishwasher machines, these additives comprising, for example, cleansing agents, washing agents, care agents, decalcifiers and rinse agents as well as supplementary additives such as active chlorine or bleach. The additives are generally supplied as solids in the form of free-flowing powders, powders compressed into tabs, as gels or as liquids. The amounts of additives required in each case must usually be added manually by the user before the beginning of each cleaning cycle, apart from rinse agents, for example, the proportions of the individual agents being fixedly preset with regard to the actual requirement. Only the rinse agent is stored in highly diluted form in storage containers for several applications and automatically added via a dosing device provided that no combination product with integrated rinse agent fraction is used.
The additives for dishwasher machines used in the prior art, in particular cleansing agents, consist of a mixture of different substances or basic chemicals with different, in each case very special tasks. The additives used so far, whether these be supplied manually or automatically, are “all-round products” or “combination products” which are designed for a very broad spectrum of applications. A specific selection of the different substances or basic chemicals required for a particular application or process step, e.g. for the “cleaning” program step, is therefore not possible because so much additive would need to be added until the portion of the substance or basic chemical required for every conceivable common domestic application is reached.
For example, cleansing agents used is the prior art as compact cleansers for dishwasher machines consist of the following basic chemicals as additives: non-ionic tensides (wetting agents), phosphates (builders), soda and silicates (alkali carriers), perborate and TAED (bleaching agents), amylase and protease (enzymes) as well as anti-foam agents, softeners, fragrances, dyes, disintegrants and coatings/binders (adjuvants not directly involved in the cleansing process). For the removal of vegetable fat, for example, from dishes in the “cleaning” program step in a dishwasher machine, however, only builders and alkali carriers are required. All the other components are disadvantageously not required in this program step, i.e. they are added without actually being necessary.
As a rule, therefore, a disadvantageous quantitative overdosing is required both during manual and automatic addition of the “all-round product”, e.g. as an all-round cleaner in order to ensure the minimum quantity of the required fraction of the basic chemicals required for the specific application. Other basic chemicals of the additive are, for example, little involved or not all involved in the cleaning process. These disadvantageously pollute the environment to a considerable extent due to the large number of dishwasher machines and their frequent use. Furthermore, high costs are thereby incurred for the user of dishwasher machines for the acquisition of basic chemicals in the additives which are used unnecessarily.
In general, liquid rinse agents are generally used in dishwasher machines which, as a result of the required dosing accuracy, consist of about 97 vol. % water and only 3 vol. % is effectively active as rinse agent in order to achieve a higher dosing accuracy because harmful excess foaming of the dishwasher occurs in the event of overdosing.
In order that only the basic chemicals needed for the respective requirement, in particular basic chemicals of all-round products, need to the added to the washing container in dishwasher machines, a dishwasher machine with a dosing device for adding additives to the washing container is proposed in DE 103 58 969.4 of the applicant in which at least one basic chemical used for clear rinsing and/or at least two basic chemicals together but not all the basic chemicals of an all-round product together and/or at least one reaction mixture of basic chemicals can be added independently. The basic chemicals are added by means of a conveying device, in particular a micro-dosing pump, e.g. a flexible tube or gear pump to a micro-reactor to produce the reaction mixture by a chemical reaction and/or to the washing container. The addition parameters, time and quantity of basic chemicals for a process step are regulated depending on the program steps and/or the actual contamination which is detected automatically with sensors or manually. The components or basic chemicals can thus be optimally dosed because a specific dosage according to time and quantity is possible. The basic chemicals are added at the optimal time point within the process step in each case and the optimal quantity is also added in each case. The basic chemicals are stored in refillable or exchangeable storage containers which are preferably constructed in the form of a common housing with partition walls or in individual separate units.
The additives described in the prior art require an actuator in the dosing device as a drive for the conveying device. In the prior art, these actuators are, for example, electric motors or other drive members which are expensive and require maintenance. A large number of actuators is normally required to add a large number of different additives to the added separately so that the disadvantage of the actuators known from the prior art is thereby amplified.